HALIFAX -- After serving 18 years in the Nova Scotia legislature, former NDP cabinet minister Maureen MacDonald announced Tuesday she is retiring from politics, saying her biggest regret is the party's failure to win a second mandate after its historic win in 2009.

"I believe that we were a very good government and we did a lot of very good things and that is becoming increasingly obvious to people under the current regime," she told a news conference at the legislature.

"That would be my one regret ... We have suffered a setback. But we will regroup and we will recover."

MacDonald was first elected to represent Halifax Needham in 1998 and held many cabinet posts, including health and wellness, finance, Gaelic affairs and African Nova Scotia affairs.

More importantly, she was named the province's first female minister of finance in then-premier Darrell Dexter's government, and introduced a balanced budget in spring 2013.

She also served as interim party leader after the New Democrats lost the general election in October 2013 to the Liberals.

MacDonald said she is stepping away from public life because her ongoing health concerns are keeping her from doing a job that requires attention around the clock.

"It's become harder for me to do that," she said. "I've been here a long time. I've worked very hard."

She said she has no problem with the direction of the party under its new leader, Gary Burrill, who was elected in February.

On another front, MacDonald said democracy in the Maritime province has been hurt by the erosion of mainstream media coverage.

"Having two newspapers, for example, when I came here offered a much higher quality of commentary and news coverage than we have seen recently," she said, referring to the demise of the Halifax Daily News in 2008.

MacDonald also mentioned the work stoppage at the daily Halifax Chronicle Herald, where newsroom staff have been on strike for more than 11 weeks.

"I am more than a little concerned about the protracted labour dispute between the Herald and their excellent, professional newsroom staff. That does not serve the democracy of this province well."

Premier Stephen McNeil said he didn't agree with that.

"I don't know if I would say democracy has been eroded -- it certainly has been evolving," he said, adding that the number of media outlets covering the legislature plunged between 2003 and 2009.

"While it's concerning when you see a labour issue that has gone on for as long as the one has at the Herald, I don't think it's eroding democracy."

Looking back, MacDonald recalled dealing with the H1N1 flu pandemic in 2009, working on new rules for all-terrain-vehicle use after two girls were killed in a crash in 2005 and, more recently, taking part in large demonstrations over the Liberal government's decision to scrap a film industry tax credit.

MacDonald said her best day as a politician came in May 2012 when, as health minister, she released the province's first, five-year mental health and addictions strategy.

Her toughest day was April 17, 2012 -- the day after gay rights activist Raymond Taavel was found beaten to death outside a bar in Halifax. Taavel was one of MacDonald's constituents.

McNeil said MacDonald enjoyed a distinguished career as a legislator.

"I had a great admiration for her," McNeil said. "I always found her extremely capable and respected her ability .... It was the health-care file where her passion seemed to be."

Before getting into politics, MacDonald was a professor of social policy at the Maritime School of Social Work.

She said she had no immediate plans, aside from some travelling and eventually returning to "civic life," though she ruled out running for municipal office.